卫星定位导航系统在地震应急救援中的应用   总被引：3，自引：0，他引：3  

曲国胜  赖俊彦  宁宝坤 《震灾防御技术》2007,2(4):409-416

在对地震灾害特点综合分析的基础上,分析了地震应急响应与救援决策中的关键性问题。认为震害的规模、程度、空间分布和灾情发展趋势,以及快速获取灾情信息已成为整个地震应急响应和救援决策的关键;而对灾情空间分布及其不同灾情程度位置的确定是救援决策的先导与重要环节。卫星定位导航技术在地震应急搜救的信息快速获取、应急响应、救援决策、指挥、搜索与营救等救援行动的整个过程中,都将发挥其强大的功能。建议研发中国北斗灾害应急救援导航与指挥决策系统,包括地震灾情快速获取、快速判定和决策定位导航技术系统、地震救援指挥调度技术系统和应急救援物流定位导航技术系统建设;研发北斗灾害应急救援导航装备,包括自主定位导航幸存者搜索和营救设备研发和国内外巨灾救援专用定位与导航系统研发。  相似文献   

Donald V. Helmberger,the master mentor: Testimonials from former international students          下载免费PDF全文

Xiaodong Song  Sidao Ni  Ying Tan  Alex Song  Risheng Chu  Daoyuan Sun  Shengji Wei  Semechah Lui  Voon Hui Lai 《地震科学（英文版）》2022,35(1):67-70

Don trained many Ph.D.students over the～5 decades of his career,at least 45 were advised or co-advised according to a Caltech account.A large number were intern...  相似文献   

Size variation of the end Permian conodont <Emphasis Type="Italic">Neogondolella</Emphasis> at Meishan Section,Changxing, Zhejiang and its significance     

Luo?Genming  Lai?Xulong?Email author  Jiang?Haishui  Zhang?Kexin 《中国科学D辑(英文版)》2006,49(4):337-347

This study is based on both a generic and species level investigation of the individual size of the latest Permian conodont Neogondolella Pa elements collected from Meishan Section A, Changxing, Zhejiang Province. In this study, an obvious size reduction of Neogondolella Pa elements within bed 24e of the upper Changxing Limestone is recognized. The size variation of the Neogondolella occurs simultaneously with some important events including the negative shift of δ ¹³C, change in the ratio of the abundance of cyanobacterial biomarkers versus that of other general bacterial biomarkers and the shallowing of the sea water. Through the investigation of the paleoenvironmental changes and the analysis of the paleoecology of the conodont genus Neogondolella, the authors propose that the major factors for the size reduction of species of the conodont genus Neogondolella are food shortages caused by the mass extinction, the shallowing of the sea water as well as the increase in opacity of the sea water during the end Permian. The same phenomenon of Neogondolella size reduction is also observed in preliminary research from the same horizon at Shangsi Section, Sichuan Province. All the evidence suggests that there was a mass extinction that occurred at the horizon of bed 24e, and the evidence supports the viewpoint of a multi-phase mass extinction during the Permian and Triassic transition in South China.  相似文献   

实时精密单点定位中周跳探测的方法研究     

梁寅 《四川测绘》2012,(3):114-116,134

实时GPS技术在诸如导航、短期天气预报、精密定位定轨等领域有着重要的现实意义,是当前GNSS领域研究的热点之一。其中,实时GPS数据预处理的质量至关重要,能否进行有效的周跳探测与修复是直接关系到GPS数据预处理质量的重要因素。本文介绍了非差模式下联合使用多种周跳探测方法（geometry—free组合、WM组合、载波相位模糊度残差）进行周跳的实时探测方法,并使用事后数据模拟实时对GPS测量数据进行了大量的验算。结果表明,此方法可以有效地探测和修复周跳,并一定程度上改善实时精密定位的精度。  相似文献   

1961-2010年三江源地区气温变化与突变分析(英文)     

易湘生  李国胜  尹衍雨 《地理学报(英文版)》2012,22(3):451-469

In this study, a monthly dataset of temperature time series (1961-2010) from 12 meteorological stations across the Three-River Headwater Region of Qinghai Province (THRHR) was used to analyze the climate change. The temperature variation and abrupt change analysis were examined by using moving average, linear regression, Spline interpo-lation, Mann-Kendall test and so on. Some important conclusions were obtained from this research, which mainly contained four aspects as follows. (1) There were several cold and warm fluctuations for the annual and seasonal average temperature in the THRHR and its three sub-headwater regions, but the temperature in these regions all had an obviously rising trend at the statistical significance level, especially after 2001. The spring, summer, autumn and annual average temperature increased evidently after the 1990s, and the winter average temperature exhibited an obvious upward trend after entering the 21st century. Except the standard value of spring temperature, the annual and seasonal temperature standard value in the THRHR and its three sub-headwater regions increased gradually, and the upward trend for the standard value of winter average temperature indicated significantly. (2) The tendency rate of annual average temperature in the THRHR was 0.36℃10a?1, while the tendency rates in the Yellow River Headwater Region (YERHR), Lancangjiang River Headwater Region (LARHR) and Yangtze River Headwater Region (YARHR) were 0.37℃10a?1, 0.37℃10a?1 and 0.34℃10a?1 respectively. The temperature increased significantly in the south of Yushu County and the north of Nangqian County. The rising trends of temperature in winter and autumn were higher than the upward trends in spring and summer. (3) The abrupt changes of annual, summer, autumn and winter average temperature were found in the THRHR, LARHR and YARHR, and were detected for the summer and autumn average temperature in the YERHR. The abrupt changes of annual and summer average temperatures were mainly in the late 1990s, while the abrupt changes of autumn and winter average temperatures ap-peared primarily in the early 1990s and the early 21st century respectively. (4) With the global warming, the diversities of altitude and underlying surface in different parts of the Tibetan Plateau were possibly the main reasons for the high increasing rate of temperature in the THRHR.  相似文献   

A multi-index coupling system of ice slope stability and its application     

WanSheng Pei  YuanMing Lai  MingYi Zhang  HongYu Xu  Wu Chen 《寒旱区科学》2012,4(3):0185-0194

Based on the Simplified Bishop Method, the minimum safety factor of ice slope both with and without tension cracks is calculated in combination with triaxial compression tests. It is found that there exists a critical depth for each crack. Then, factors influencing ice slope stability such as slope ratio, slope height, ice cohesion, internal friction angle, unit weight and temperature were analyzed. Meanwhile, a regression equation between the aforementioned factors and safety factor is obtained, with which sensitivity analysis is carried out. The performance function is built in combination with random distribution of physical and mechanical parameters to analyze the reliability index. The Advanced First Order Second Moment Method is employed on the solution to the performance function. The one-way coupling system of ice slope stability is therefore formed based on safety factor and reliability index. Finally, an illustrated example of ice slope is provided, which shows that failure probability is relatively high, up to 6.18%, although safety factor is 2.77. Thus, it is objective and reasonable to apply the coupled system method to the slope stability rating.  相似文献   

Influence of the 11-Year Solar Cycle on Variations of Cosmic Ray Intensity     

L. H. Ma  Y. B. Han  Z. Q. Yin 《Solar physics》2009,255(1):187-191

The monthly cosmic ray intensity (CRI) time series from Climax, Huancayo, Moscow, Kiel, and Calgary are used to investigate the presence of the 11-year periodic component with special attention paid to the solar influence on these variations. The results show obvious 11-year temporal characteristics in CRI variations. We also find a close anticorrelation between the 11-year solar cycle and CRI variations and time delays of the CRI relative to solar activity.  相似文献   

Elevation dependency of recent and future minimum surface air temperature trends in the Tibetan Plateau and its surroundings   总被引：10，自引：0，他引：10  

Xiaodong Liu  Zhigang Cheng  Libin Yan  Zhi-Yong Yin   《Global and Planetary Change》2009,68(3):164-174

Elevation dependency of climate change signals has been found over major mountain ranges such as the European Alps and the Rockies, as well as over the Tibetan Plateau. In this study we examined the temporal trends in monthly mean minimum temperatures from 116 weather stations in the eastern Tibetan Plateau and its vicinity during 1961–2006. We also analyzed projected climate changes in the entire Tibetan Plateau and its surroundings from two sets of modeling experiments under future global warming conditions. These analyses included the output of the NCAR Community Climate System Model (CCSM3) with approximately 150 km horizontal resolution for the scenario of annual 1% increase in atmospheric CO₂ for future 100 years and physically-based downscaling results from the NCAR CAM3/CLM3 model at 10' × 10' resolution during three 20-year mean periods (1980–1999, 2030–2049 and 2080–2099) for the IPCC mid-range emission (A1B) scenario. We divided the 116 weather stations and the regional model grids into elevation zones of 500 m interval to examine the relationship of climatic warming and elevation. With these corroborating datasets, we were able to confirm the elevation dependency in monthly mean minimum temperature in and around the Tibetan Plateau. The warming is more prominent at higher elevations than at lower elevations, especially during winter and spring seasons, and such a tendency may continue in future climate change scenarios. The elevation dependency is most likely caused by the combined effects of cloud-radiation and snow-albedo feedbacks among various influencing factors.  相似文献   

Cosmogenic production as a background in searching for rare physics processes     

D.-M. Mei  Z.-B. Yin  S.R. Elliott 《Astroparticle Physics》2009,31(6):417-420

We revisit calculations of the cosmogenic production rates for several long-lived isotopes that are potential sources of background in searching for rare physics processes such as the detection of dark matter and neutrinoless double-beta decay. Using updated cosmic-ray neutron flux measurements, we use TALYS 1.0 to investigate the cosmogenic activation of stable isotopes of several detector targets and find that the cosmogenic isotopes produced inside the target materials and cryostat can result in large backgrounds for dark matter searches and neutrinoless double-beta decay. We use previously published low-background HPGe data to constrain the production of ³H on the surface and the upper limit is consistent with our calculation. We note that cosmogenic production of several isotopes in various targets can generate potential backgrounds for dark matter detection and neutrinoless double-beta decay with a massive detector, thus great care should be taken to limit and/or deal with the cosmogenic activation of the targets.  相似文献   

Spectral hardness evolution characteristics of tracking gamma-ray burst pulses     

Z.Y. Peng  L. Ma  R.J. Lu  L.M. Fang  Y.Y. Bao  Y. Yin 《New Astronomy》2009,14(3):311-320

Employing a sample presented by Kaneko et al. (2006) [Kaneko, Y. et al., 2006. ApJS 166, 298 (Paper I)] and Kocevski et al. (2003) [Kocevski, D. et al., 2003. ApJ 596, 389], we select 42 individual tracking pulses (here we defined tracking as the cases in which the hardness follows the same pattern as the flux or count rate time profile) within 36 gamma-ray bursts (GRBs) containing 527 time-resolved spectra and investigate the spectral hardness, E_peak (where E_peak is the maximum of the νF_ν spectrum), evolutionary characteristics. The evolution of these pulses follow soft-to-hard-to-soft (the phase of soft-to-hard and hard-to-soft are denoted by rise phase and decay phase, respectively) with time. It is found that the overall characteristics of E_peak of our selected sample are: (1) the E_peak evolution in the rise phase always start on the high state (the values of E_peak are always higher than 50 keV); (2) the spectra of rise phase clearly start at higher energy (the median of E_peak are about 300 keV), whereas the spectra of decay phase end at much lower energy (the median of E_peak are about 200 keV); (3) the spectra of rise phase are harder than that of the decay phase and the duration of rise phase are much shorter than that of decay phase as well. In other words, for a complete pulse the initial E_peak is higher than the final E_peak and the duration of initial phase (rise phase) are much shorter than the final phase (decay phase). This results are in good agreement with the predictions of [Lu, R.J. et al., 2007. ApJ 663, 1110] and current popular view on the production of GRBs. We argue that the spectral evolution of tracking pulses may be relate to both of kinematic and dynamic process even if we currently can not provide further evidences to distinguish which one is dominant. Moreover, our statistical results give some witnesses to constrain the current GRB model.  相似文献